在标准ASCIl码表中,已知英文字母A的ASCIl码是01000001,英文字母D的ASCIl码是( )。
A. 01000011
B. 01000100
C. 01000101
D. 01000110
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[A] What route does HIV take after it enters the body to destroy the immune system[B] How and when did the long-standing belief concerning AIDS and HIV crop up[C] What is the most effective anti-HIV therapy[D] How does HIV subvert the immune system[E] In the absence of a vaccine, how can HIV be stopped[F] Why does AIDS predispose infected persons to certain types of cancer and infections In the 20 years since the first cases of AIDS were detected, scientists say they have learned more about this viral disease than any other. Yet Peter Piot, who directs the United Nations AIDS program, and Stefano Vella of Rome, president of the International AIDS Society, and other experts say reviewing unanswered questions could prove useful as a measure of progress for AIDS and other diseases.Among the important broader scientific questions that remain:41. A long-standing belief is that cancer cells constantly develop and are held in check by a healthy immune system. But AIDS has challenged that belief. People with AIDS are much more prone to certain cancers like non-Hodgkins lymphomas and Kaposi"s sarcoms, but not to breast, colon and lung, the most common cancers in the United States. This pattern suggests that an impaired immune system, at least the type that occurs in AIDS, does not allow common cancers to develop.42. When HIV is transmitted sexually, the virus must cross a tissue barrier to enter the body. How that happens is still unclear. The virus might invade directly or be carried by a series of different kinds of cells. Eventually HIV travels through lymph vessels to lymph nodes and the rest of the lymph system. But what is not known is how the virus proceeds to destroy the body"s CD-4 cells that are needed to combat invading infectious agents.43. Although HIV kills the immune cells sent to kill the virus, there is widespread variation in the rate at which HIV- infected people become ill with AIDS. So scientists ask: Can the elements of the immune system responsible for that variability be identified If so, can they be used to stop progression to AIDS in infected individuals and possibly prevent infection in the first place44. In theory, early treatment should offer the best chance of preserving immune function. But the new drugs do not completely eliminate HIV from the body so the medicines, which can have dangerous side effects, will have to be taken for a lifetime and perhaps changed to combat resistance. The new policy is expected to recommend that treatment be deferred until there are signs the immune system is weakening. Is a vaccine possible There is little question that an effective vaccine is crucial to controlling the epidemic. Yet only one has reached the stage of full testing, and there is wide controversy over the degree of protection it will provide. HIV strains that are transmitted in various areas of the world differ genetically. It is not known whether a vaccine derived from one type of HIV will confer protection against other types.45. Without more incisive, focused behavioral research, prevention messages alone will not put an end to the global epidemic.
So what is depression Depression is often more about anger turned【C1】______than it is about sadness. But it"s usually【C2】______as sadness. Depression can【C3】______at all ages, from childhood to old age, and it"s the United States" No.【C4】______problem. When someone is depressed, her behavior【C5】______change and she loses interest in activities she【C6】______enjoyed (like sports, music, friendships). The sadness usually lasts every day for most of the day and for two weeks or more. What【C7】______depression A【C8】______event can certainly bring【C9】______depression, but some will say it happens【C10】______a specific cause. So how do you know if you"re just having a bad day【C11】______are really depressed Depression affects your【C12】______, moods, behavior and even your physical health. These changes often go【C13】______or are labeled【C14】______simply a bad case of the blues. Someone who"s truly【C15】______depression will have【C16】______periods of crying spells, feelings of【C17】______(like not being able to change your situation) and【C18】______(like you"ll feel this way forever) , irritation or agitation. A depressed person often【C19】______from others. Depression seldom goes away by itself, and the greatest【C20】______of depression is suicide. The risk of suicide increases if the depression isn"t treated. 【C4】
A. social
B. academic
C. literary
D. health
下面关于肝素的描述,哪一项是错误的
A. 肝素为硫酸黏多糖类物质
B. 抗凝作用主要表现为抗FXa和凝血酶
C. 抗凝机制与蛋白C系统密切相关
D. 肝素还有促进内皮细胞释放t—PA,增强纤溶活性的作用
E. 主要由肺或肠黏膜肥大细胞合成
根据我国现行《宪法》和《立法法》,下列选项中哪一行为与宪法或法律不相抵触______
A. 全国人民代表大会通过决议决定某直辖市进入紧急状态
B. 全国人民代表大会常务委员会授权国务院制定行政法规规定犯罪与刑罚
C. 全国人大常委会撤销某直辖市人民代表大会制定的同宪法相抵触的地方性法规
D. 全国人大专门委员会撤销某省人民代表大会制定的同法律相抵触的地方性法规